Metal spray gun



oct. 19, 1937. R, ENSCH ET AL 2,096,119

METAL SPRAY GUN fnvengnsf Iadofiz elzsch and Paal Zedez METAL "SPRAY GUN A, mec; April 11s,. 193e y :s sneetssneet 2 f2 l waz V l ,l

if and fdlllled' R. LENscHvETAl. 2,096,119 l METAL SPRAY GUN Filed April 13, 1936 l v 3 Sheets-Sheet 5 -Iuvenrs Iudolph Lems'ch and 'Patented Oct. 19, 1937 UNITED STATES 2,096,119 ivmTAL SPRAY GUN Rudolph Lensch, Los Angelis, and Paul Leder, Alhambra, Calif.

Application April 13,

4 Claims.

The hereinafter described invention relates to the spraying of molten metal, being characterized by improvements in devices for this purpose, which devices utilize gaseous fuels for melting the 5 metal as fed through them in wire form and iiuid pressure for atomizing and depositing the molten metal against a base or part to be metal coated.

Among the objects of this invention is the provision of certain new and novel features and ad- 1,0 vantages beyond the improvements in Metal fspraying devices as set out in United States Letters ,Patent granted to Rudolph Lensch and Paul Leder, January 8, 1935, No. 1,987,016.

One of the objects of the present invention is to provide an improved arrangement of controlling the wire fed through the gun whereby any desired pressure may be exerted on the wire in its passage through the wire feeding Wheels, thereby better preventing slippage of the wire and effecting through the uniformity of its feed an improved quality of the molten metal deposition.

Another object of this invention is to provide a hinged latch construction whereby the top wire feeding wheel is releasably confined so that during wire feeding it can be set to engage the wire and after or during wire feeding can be unlatched and lifted on its hinged connection out of the way.

Another object of this invention is to increase the eiciency of the power plantas employed for driving the wire feeding mechanism of the gun through improvements, (1) in the turbine used as the prime mover, and -(2) in the gearing of the transmission, the housing of the transmission and the manner of` setting the transmission gearing in its bearings.

A further object of this invention is to form the combustion unit of the gun as a separate and distinct entity from the the mechanical unit or power plant of the gun and to so provide conduits for carrying the iiuid for atomizing the molten metal of the gun as well as the fuel for melting the metal that they Will be contained in a single unit, one end of which terminates in a base to which the fuel nozzle of the gun is attached, and the opposite end of which terminates in the valve controlling means for the fluid pressure and fuel in its pas- 0 sage through the unit-thereby (1) condensing the space which these conduits occupy, eliminating joints subject to leakage and permitting of a construction of relatively light weight, and (2) making a construction for carrying fluid pressure 55 and fuel which can be assembled in the gun as ,a

1936, serial No. 74,028

(c1. sii-12.2)

unit as well as replaced as a unit for expeditiousv repair.

Another object of this invention is to provide in a metal spray gun a casting as an integral part which will contain the housings for encompassing the gears of the transmission as well as the turbine for driving the transmission gears and to so form the casting that it will have a channel way for the wire feed, free and clear of the interiors of the gear and turbine housings.

Another object of our invention is to provide a new and novel way of handling the turbine exhaust, so that the exhaust will be expanded between the cover of the turbine and the turbine impeller and released through openings in the turbine cover, and after passing through these openings will be baffled to effect its discharge circumferentially, thereby 'effecting a greater' efficiency of the turbine through the improved means vof governing its exhaust.

A further object of this invention is to improve the efficiency of the combustion unit of the gun through the provision of .a baiiiing arrange- In order to more fully understand our invention I reference should be made to the accompanying drawings, in which Eig. 1 is a side elevation with portions broken away and certain parts in section to better illustrate the improvements. Fig. 2 is a side elevation of the upper portion only of the structure of our invention, this view showing the side directly opposite the side of the elevation of Fig.- 1. Fig. 3 is a sectional plan view taken on line 3-v3, Fig. 2. Fig. 4 is arear end elevation of the upper portion only of our improved structure. Fig. 5 is a broken perspective view ofthe wire feeding mechanism of our improvements. Fig. 6 also shows in sectional side elevation another view of the improved wire feeding arrangement of our structure taken on line 5-6, Fig. 4.

Fig. 'l is a side'elevation showing the combustion unit only of our improved gun structure, While Fig. 8 is a rear-end view of the upper portion thereof.

Referring to the drawingst-Description willY justably confined endwise by threaded containers I6 and I1 respectively. Containers I6 and I1 are locked in position after adjustment by lock nuts' 'at its opposite ends. The bearings 23 and`24/are aligned` so as to bring the worm wheel 2| into meshed engagementwith -the worm I3 of turbine shaft I2. Shaft 26 isadjustably confined endwiseV through the threaded engagement of bearing 23 with casting II) on the one end and through the threaded engagement of bearing 24 on the opposite end as provided in the gear chamber cover 25. Locknuts 26 and 21 confine the bearings 23 and 24 respectively, in adjusted position. Numeral 28 denotes a shaft substantially at right angles to shaft 20. shaft-28 canies a worm wheel 29, and is mounted in bearings 30, 3| and 32 so as to bring worm wheel. 29 into meshed engagement-with the worm 22 of shaft 20. Shaft 28 is adjustably conned endwise through the threaded engagement of bearing 38 as provided in the gear chamber cover 32a. A lock nut 33 confines the bearing 30 in adjusted position. Shaft 28, termed as the wire feed shaft, carries a wire feeding wheel cornprising two portions, 34a.l and 34h. Portion 34a consists of a spur gear, while portion 34b consists of a grooved knurl wheel. Situated immediatelyv over the wire feeding wheel of shaft 28 is another similar wire feeding wheel, comprising portions 35a and 35h. Portion 35a consists of a spur gear adapted to mesh with the spur gear 34a, while portion 35o consists of a knurled wheel adapted to cooperate with the knurled wheel 34b in the feeding of the wire through the gun as hereinafter described. 'Ihe wire feeding wheels, comprised of the parts 34a-34h and 35o-35h are known as the lower and upper wire feeding wheels, respectively. The meshing of the gear portions of the wire feeding wheels is brought about only during the feeding of wire and through a new and novel arrangement of parts involvinga latch device pivotally mounted in bearing plates 36 and 31 `secured to lugs Ina and lub of casting I0. 'I'he pivotal. mounting is occasioned by a.. shaft 38..flt

ting bearlngsmade in the plates 36 and 31. Shaft 3 8 carries a part 39, having depending portions containing bearings for carrying a shaft 40a upon which is mounted the upper wire feeding wheel 35u-35h. Secured to the top of part 39 by bolt 4I is a latch member 42 having wing portions 42a and 42b extending from its side. The member 42 is adapted to swivel on the boit 4I Now, secured to the bearing plates 36 and 31, respectively, are two forked members 43 and 44. These forked members have open jaws, the jaws being set so that their open ends are opposed to each other. The jaws of members 43 and 44 are adapted to receive the wing portions 42a and 42h of latch member 42, the cooperating edges of the wings and `jaws being beveled so that when the latch member 42 is swiveled `in its connection a firm but releasably confined engagement of member 42 Will be made in the jaws of members 43 and 44. In this latch construction it will be noted that the depending bearing portions of part 39A carrying the upper wire' feeding wheel 35u-35h, are adapted to nt between the faces ,.Ic and Ind of the main casting ID- a channel being formed between said faces of casting III to receive the part 39 when the latch member 42 is engaged in the wheel and the gear portion 34a of the lower wire feeding wheel are brought into meshed engagef ment for the feeding of wire through the knurled portions 34h and 35h of the respective wire feeding wheels. A spring tension device is provided in the latch member 42 which gives the ability to the latch structure to adjust the pressure applied upon the wire in its feed through the knurled portions 34b and 35h of the lowerand upper wire lfeeding wheels, respectively. This device comprises a spring 45 chambered in latch member 42, the upper end of member 42 being tapped to receive'a spring tension adjusting screw 46.

In the drawings, Fig. 1, the latch device is shown in dotted lines swung up in the out of service position, that is, when no wire is being fed through the gun. By our improved structure the operator has a full vision of the wire, from the time of its entrance through the rear wire guide 4-1 and across the face of the knurled portion 34h of the lower wire feeding Wheel into the front wire guide 48, before the latch member 42 is dropped down on its pivotal mounting into the channel way of the main casting I0 and its wings 42a and 42b are locked in wire feeding position in the jaws of members 43 and 44. 'I'he improved wire feeding an'angementof our structure including the latch device and channel between the sides IIIc and Idd of main casting III, for receiving the latch member 42 and upper wire feeding wheel as depended therefrom, is well shown in perspective view Fig. 5, while'the sectional illustration of Fig. 6 shows the structure in functioning position during the feeding of wire.

Having described the wire feeding structure of our invention we willl proceed with the description of the combustion unit thereof andy in this connectionreference is made particularly to Fig. 1, Figs. 7 and 8, in which Fig. 1 shows this unit assembled in place in the gun structure, and Fig. 7 shows the combustion unit formed'as a separate entity ready for insertion into the gun assembly. Numeral 49 denotes the nozzle base member and numeral 59 the compressed air and fuel manifold member-these members forming the termini of outlet thereof, 52, being adapted to carryo' a -f portion of the compressed air to the turbine impeller II through the passage 52a in main casting I8. Conduit 53 and conduit 54 carry respectively the oxygen and acetylene used as fuel. Conduit 53 and conduit 54 are united together by a combining chamber 55-out of which a conduit 56 leads these mixed gases. The lower ends of the conduits 5I, 53 `and 54 are made up in fluid tight joint engagement to manifold member- 56, while the upper ends of the conduits 5I and larly made up in joint engagement with nozzle base 49. In this structure a definite distance is maintainedbetween the nozzle base 49 and the manifold 50 and the conduits 5I, 53, 54 and 56 may all be removed and replaced in the gun assembly at one time. This makes for an eiliciency in a metal spray gun not heretofore possible through the ability to expeditiously'replace the combustion unit of the gun in the event of failure of the gaseous passages thereof. Numerals 51, 56 and 59 denote respectively the compressed' air, oxygen and acetylene valves used for controlling the' gaseous fluids of the combustion unit, the same being made up to manifold 50. Furthermore by our improved unit assembly of the uid carrying conduits of the gun, a more compact and simplied gun structure is effected.

In the assembly of the unit in the gun a hollow screw 62, tapped into casting IU, through which compressed air leads into passage 52a, together with the screws 63 passing through the hole 64 in nozzle base member 49 and fitting tapped holes in casting I0, hold the unit in releasably confined position in the gun assembly.

Nozzle base 49 is threaded at 49a and 49h, the threadv 49h being adapted to receive a threaded union nut 65 holding the gun nozzle St in position. Encompassing nozzle 66 and secured to threaded end 49a of nozzle base 49 is air funnel 61. The smaller'end of funnel 61 is adapted to receive the air cap 68 through threaded engagement between these respective parts. Lock nut 69 retains the air cap 68 in adjusted position in its threaded engagement with funnel 61. It will be noted that a baille plate 10 is carried by the Junion nut 65. Bafile 10 is provided with a plurality of openings 1I through which the compressed air from the conduit 5l of the combustion unit is checked and deflected around the vnozzle 66 and through the funnel 61 and air cap 68 in a highly efficient manner in effecting the atomization of the molten metal.

In the improved turbine structure of our invention numeral H denotes the turbine impeller as fixed tothe turbine shaft I2. Main casting I0 is chambered to receive impeller Il, a threaded rim being provided on the' impeller chamber to receive the threaded turbine cover 14. Turbine impeller Il is provided with a cavity between the inner circumferential edge bounding its buckets 15 and its hub 16-this space providing what we choose to term the turbine impeller expansion chamber. Now in the turbine casing cover 14 and. directly opposite the expansion chamber of 40 impeller Il, is a chamber portion carrying a plurality of openings around it as denoted by numeral 11. Openings 11 are preferably of like size and inclined upwardly. Numeral 18 denotes a cup-like baffle secured to turbine cover 14 through the medium of lock nut -I8 of. the ball bearing container I6. Baiiie 18 is set so as to provide a circumferentially extending slot 19 between its cupped edge 18a and the face 14a of turbine cover 14, thereby providing a free discharge for the air as exhausted from impeller ii through the openings 11 of turbine casing cover 14.

From the foregoing description it will be clear.

that the air as exhausted from the buckets 15 of turbine impeller ll is held a relatively long time between the chambered portions of the impeller and the turbine cover 14 before its final release to the atmosphere through the slot 19.

During this time an expansion of the air is occasioned without creating undue back-pressure.

By retaining the air lexhausted fromthe turbinev impeller in this manner we have found that the initial air introduced through the passage 52a 65 against the buckets vof the impeller is utilized with high eiciency and that a. much less pressure of compresed air is required to drive the turbine impeller than heretofore used, for example in the` turbine structure of our invention ascovered 70 by Letters Patent No. 1,987,016.

The compressed air through the passage 52a as used for driving impeller Il is `controlled through needle valve 811.

The combustion unit of our structure is housed by the handle of the gun, the same being comprised of parts 8l and 82 removably confined by the screws 83, 84 and 85.

We desire it to be understood that reasonable modifications in the structural improvements of our invention, as shown by the illustrative embodiments herewith, may be made without departing from the spirit thereof and we therefore do not wish to restrict ourselves to the exact showing made, the scope of the invention being governed by the extent of the appended claims.

We claim:

1. In a metal spray gun, of the class described,-

of compressed air from said nozzle base, an air funnel encompassing said nozzle and baffle and an air cap secured `to the end of said funnel.

2. -In a metal spray gun, a powerv unit compris- 'ing a member adapted to carry a turbine, transmission gears, and wire feeding wheels, said member including housings for said turbine and gearsand an open channel in its walls exteriorly of said housings, said wheels being adapted for rotation in said channel, a combustion unit comprising a member adapted to carry combustible gases and compressed air, and having control valves and a nozzle base, a metal spraying nozzle secured to said base and adapted to receive the gasesand compressed air of the combustion unit, and means including an abutment between the nozzle base and the walls of said member for releasably confining said units in operative association whereby saidy wire feeding whjeels are visibly disposed in said channel.

3. In a metal spray gun, a power'unit comprising a member adapted to carry a turbine, transmission gears anda pair of wire feeding wheels, said member providing housings for said turbine and gears and having an open channel in its Walls between said housings', one of said Wire feeding wheels being mounted on a shaft extending from the transmission gears beyond the housing thereof and adapted to rotate in said channel, the other of said wire feeding wheels being pivotally mounted on said member and adapted for rotation in said channel, and means for holding the said wire feeding wheels in cooperative engagement during the feeding of wire. 4. A wire feeding mechanism for a metal spray gun comprising a member having a turbine, transmission gears, and a pair of wire feeding wheels, means for effecting the visible feed of wire through said wheels comprising: an open channel in the walls of said member between the turbine andgear housings thereof, a wire feeding wheel mounted between the sides of said channel and actuated by said transmission gears, a Wire feeding wheel hingedly mounted on said member and adapted for rotation in said channel, and a spring latch for holding said hingedly mounted wire feeding Wheel in engagement with said first wire feeding Wheel during the feeding of wire.

RUDOLPH LENSCI-I. PAULI LEDER.

2,096,119.4R1ulo'l`12. Lensch, Los Angele DISCLAIMER s, ind Paul Leder, Alhambra, METAL SPRAY GUN. Patent dated October 19, 1937. Disclaimer filed October 3, l 1942, by the inventors.

Hereby enter tln `'s disclaimer' to claims 2, 3, and 4 in said Specicatioil., [Oficial Gazette November 3, 1.942.] l l 

